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1.
Neuroimage ; 277: 120231, 2023 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-37330025

RESUMO

Estimating structural connectivity from diffusion-weighted magnetic resonance imaging is a challenging task, partly due to the presence of false-positive connections and the misestimation of connection weights. Building on previous efforts, the MICCAI-CDMRI Diffusion-Simulated Connectivity (DiSCo) challenge was carried out to evaluate state-of-the-art connectivity methods using novel large-scale numerical phantoms. The diffusion signal for the phantoms was obtained from Monte Carlo simulations. The results of the challenge suggest that methods selected by the 14 teams participating in the challenge can provide high correlations between estimated and ground-truth connectivity weights, in complex numerical environments. Additionally, the methods used by the participating teams were able to accurately identify the binary connectivity of the numerical dataset. However, specific false positive and false negative connections were consistently estimated across all methods. Although the challenge dataset doesn't capture the complexity of a real brain, it provided unique data with known macrostructure and microstructure ground-truth properties to facilitate the development of connectivity estimation methods.


Assuntos
Imagem de Difusão por Ressonância Magnética , Processamento de Imagem Assistida por Computador , Humanos , Processamento de Imagem Assistida por Computador/métodos , Imagem de Difusão por Ressonância Magnética/métodos , Encéfalo/diagnóstico por imagem , Método de Monte Carlo , Imagens de Fantasmas
2.
Psychiatr Serv ; 71(8): 796-802, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32340597

RESUMO

OBJECTIVE: This study evaluated the impact of two behavioral health home (BHH) approaches, provider-supported care and self-directed care, on health care utilization and cost outcomes among adult Medicaid recipients with serious mental illness. METHODS: Eleven community mental health provider sites were randomly assigned to one of the BHH approaches, which each site implemented over a 2-year period. In both approaches, staff were trained in wellness coaching to support patients' progress toward general health and wellness goals. Provider-supported sites employed a full-time on-site registered nurse, who provided consultation to patients and wellness coaches. Each approach had a consistently enrolled treatment group (combined N=859) with a matched comparison cohort that was identified for analysis. Approaches were compared with each other and with baseline, and differences between each approach and its comparison cohort were examined by using analysis of covariance to determine impact on total health care cost, prescription costs, and use and cost of general medical and behavioral health services. RESULTS: Relative to its comparison cohort, each approach achieved significant reductions in total cost (15% for provider-supported care and 26% for self-directed care) and increases in use of outpatient general medical services (43% for provider-supported care and 29% for self-directed care). Compared with self-directed care, provider-supported care resulted in approximately 28% lower use of general medical inpatient services and 26% lower related costs. CONCLUSIONS: BHH approaches in community mental health settings can produce health care savings and decrease use of inpatient health care.


Assuntos
Custos de Cuidados de Saúde , Transtornos Mentais/economia , Transtornos Mentais/terapia , Psiquiatria/economia , Adulto , Feminino , Humanos , Masculino , Medicaid/economia , Serviços de Saúde Mental , Autocuidado/economia , Estados Unidos
3.
Quant Imaging Med Surg ; 9(10): 1664-1673, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31728310

RESUMO

BACKGROUND: Degradation of cartilage and meniscus may be mediated by changes in extracellular pH. The purpose of this study was to optimize saturation powers used with the acidoCEST magnetic resonance imaging (MRI) technique with a 3D ultrashort echo time readout (acidoCEST-UTE) and to demonstrate feasibility of the method for measuring pH in cartilage and meniscus in vivo. METHODS: Magnetization transfer ratio asymmetry and ratio of radiofrequency (RF) power mismatch at different powers were evaluated in cartilage and meniscus tissue phantoms for iopamidol and iohexol. Using optimized RF powers, the acidoCEST-UTE MRI sequence was used to assess pH of joint fluid and tissues in four patients after direct intra-articular administration of iodinated contrast. RESULTS: In the phantoms, the ratio of powers 0.54/1.10 µT showed the strongest correlation with pH. In vivo acidoCEST-UTE pH measurements of intra-articular fluid were similar to electrode measurements of the contrast agent (7.22 vs. 7.1 for iopamidol, respectively; 7.65 vs. 7.5 for iohexol, respectively). As measured with the acidoCEST-UTE technique, overall mean cartilage pH was significantly lower than overall mean meniscus pH (6.60 vs. 6.72, respectively; P=0.043). CONCLUSIONS: AcidoCEST-UTE MRI after direct intra-articular administration of either iopamidol or iohexol can be used to measure cartilage and meniscus pH in vivo.

4.
Small ; 9(18): 3161-8, 2013 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-23468419

RESUMO

In this study, zebrafish larvae are introduced as an in vivo platform to examine the neurotoxicity and developmental toxicity associated with continuous exposure to a concentration gradient of different sizes of SiO2 nanoparticles (15 nm and 50 nm diameter) to determine the dose effect and size effect of SiO2 nanoparticle (NP)-induced toxicity. Bovine serum albumin (BSA-V) is utilized as a stabilizing agent to prevent coagulation of the SiO2 nanoparticles. To the best of our knowledge, this study is the first to describe locomotor activity assays linking rest/wake behavioral profiles for the purpose of investigating the neurotoxicity of NPs. In addition, developmental toxicological endpoints including mortality, LC50 , malformation, and cartilaginous deformity are assessed. The results show a concentration-dependent increase in behavioral neurotoxicity, mortality, and malformation among larvae treated with the SiO2 nanoparticles of 15 nm and 50 nm. A comparison of the 15 nm and 50 nm NPs by K-means clustering analysis demonstrates that the 15 nm NPs have a greater neurotoxic effect than the 50 nm NPs, with the 50 nm NPs exhibiting greater developmental toxicity on the zebrafish larvae than the 15 nm NPs.


Assuntos
Nanopartículas/toxicidade , Dióxido de Silício/toxicidade , Animais , Larva/efeitos dos fármacos , Vigília/efeitos dos fármacos , Peixe-Zebra/anormalidades
5.
Huan Jing Ke Xue ; 31(10): 2445-9, 2010 Oct.
Artigo em Chinês | MEDLINE | ID: mdl-21229759

RESUMO

Quinolone antibiotics (QNs) including norfloxacin (NOR), enrofolxacin (ENR), ciprofloxacin (CIP) and lomefloxacin (LOM) in vegetable samples collected from Guangzhou were determined by high performance liquid chromatography (HPLC) coupled with fluorescent detector (FLD). The detected frequency of QNs was 96% in vegetables. The total concentration of quinolones (sigma QNs) detected in vegetable ranged from 1.0 microg/kg to 1 683.1 microg/kg (F.W.). Leafy vegetable topped the content of quinolones among the three types of vegetables, followed by the melon-fruit vegetable and rhizome vegetable. The detected frequency of the four quinolone antibiotics ranked as NOR > CIP > LOM > ENR. Except ENR, concentrations of CIP, NOR, LOM and sigma QNs in pollution-free vegetable, green vegetable and organic vegetable were higher than those in routine cultivated vegetables. The maximum contribution to ADI value (caculated by the sum of CIP and ENR) is estimated up to 41.5% and 83% for adults and children respectively via consumption of vegetables.


Assuntos
Antibacterianos/análise , Contaminação de Alimentos/análise , Quinolonas/análise , Verduras/química , China , Cromatografia Líquida de Alta Pressão , Ciprofloxacina/análise , Fluoroquinolonas/análise , Norfloxacino/análise , Medição de Risco , Saúde da População Urbana
6.
Eur Radiol ; 19(9): 2163-70, 2009 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-19381643

RESUMO

The purpose was to compare two-dimensional (2D) magnetic resonance pancreatography (MRP) with 3D MRP to evaluate intraductal papillary mucinous neoplasm (IPMN). Thirty-four patients (22 men, 12 women; age range, 45-80 years) with IPMN (n = 40) were examined with MRP on 2D and 3D sequences. Two readers independently reviewed the images to assess the overall image quality, artifacts, lesion location, communication with main pancreatic duct, and potential for malignancy. The readers assigned their confidence level (1-5) for predicting ductal communication of the lesion. The results of MRP were compared with endoscopic retrograde pancreatography and surgical and histopathologic findings. Studies obtained with 3D MRP were of significantly higher technical quality than those obtained with 2D MRP. Although 3D MRP showed higher area under the ROC curve (Az) values for predicting ductal communication of the lesion, there was no statistical significance between Az values of 2D and 3D MRP (Az for 2D = 0.821, 0.864 for readers 1 and 2, respectively, and Az for 3D= 0.964, 0.921). Accuracies for discriminating benign from malignant lesions were 70 and 67.5% (reader 1 and 2, respectively, for 2D) and 62.5 and 80.1% (3D). 3D MRP showed superior image quality to that of 2D MRP but did not increase the diagnostic accuracy for predicting ductal communication of the lesion.


Assuntos
Algoritmos , Carcinoma Ductal Pancreático/diagnóstico , Colangiopancreatografia por Ressonância Magnética/métodos , Aumento da Imagem/métodos , Interpretação de Imagem Assistida por Computador/métodos , Imageamento Tridimensional/métodos , Neoplasias Pancreáticas/diagnóstico , Adenocarcinoma Mucinoso/diagnóstico , Idoso , Idoso de 80 Anos ou mais , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
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